1. Field of the Invention
The present invention generally relates to an optical connector, and more particularly, to an optical ring network suitable for an optical fiber communication system in a vehicle such as motor vehicle and to an optical connector and a hybrid connector which are suitable for the optical ring network.
2. Description of the Related Art
In an optical ring network connecting processing units, the unit are connected with an optical fiber and an optical connector in series, and light (an optical signal) outputted from the units are transmitted successively and stored in an addressed unit.
An optical connector used in such an optical ring network is disclosed in Japanese Patent Application Laid-open No. 10-78534.
The above optical connector will now be described, referring to FIGS. 25-26.
An optical plug 1 as the above optical connector consists of a ferrule assembly 2, a plug housing 3 to accommodate the ferrule assembly 2, a spring cap 4 to fit in the plug housing 3 and to check coming-off of the ferrule assembly 2, and a directing member 5 to pivotably engage the spring cap 4, which optical plug 1 is connected to a receptacle 7 to be an optical connector on a side of a unit 6.
The ferrule assembly 2 consists of a plastic optical fiber 8, a ferrule 9 to be provided at an end of the optical fiber 8, and a spring 10 to be inserted into the optical fiber 8. When the ferrule assembly 2 is accommodated in the plug housing 3 and then the spring cap 4 fits in the plug housing 3, the ferrule 9 is pressed toward the receptacle 7 by means of the spring 10 whose one end abuts against the spring cap 4. A hole 11 in which the optical fiber 8 is inserted is formed on the spring cap 4. The hole 11 goes through a supporting wall 12 of the spring cap 4.
The directing member 5 has a base portion 13 bending by about 90 degrees in a circular-arc. A slipping ring 15 is provided on an end of the base portion 13 through a supporting groove 14. And, a holding portion 16 is projectingly provided on the other end of the base portion 13.
A radius of the base portion 13 is set to a minimum allowable bending radius of the optical fiber 8. A gap portion 17 to facilitate attachment is formed on the slipping ring 15. The optical fiber 8 is arranged in a circular-arc along a periphery of the base portion 13 between the holding portion 16 and the slipping ring 15.
In the above structure, the slipping ring 15 of the directing member 5 is fitted on the supporting wall 12 of the spring cap 4 and then a collar portion 18 of the spring cap 4 is inserted into the supporting groove 14 of the directing member 5, whereby the directing member 5 gets pivotable with respect to the supporting wall 12 of the spring cap 4. By turning the directing member 5 in a desirable position and by arranging the optical fiber 8 in a circular-arc along the periphery of the base portion 13 between the holding portion 16 and the slipping ring 15, the optical fiber 8 can be led out in a desirable direction.
In the above prior art, the optical fiber 8 led out from the hole 11 of the spring cap 4 is arranged along the base portion 13 of the directing member 5.
With respect to the above prior art, however, there should be the following problems when leading-out direction of the optical fiber 8 is changed.
That is, when the directing member 5 is turned while the optical fiber 8 is attached to the base portion 13, the optical fiber 8 gets twisted near the hole 11 of the spring cap 4, thereby causing attenuation of the light transmitted with the optical fiber 8.
Describing the above in a little further detail, diameter of the hole 11 is merely a little larger than that of the optical fiber 8 and also reaction force of bending of the optical fiber 8 acts on the hole 11, whereby the optical fiber 8 becomes hard to turn. Therefore, when the directing member 5 is quickly turned to change a leading-out direction of the optical fiber 8, distortion force acts on the optical fiber 8.
If the diameter of the hole 11 is enlarged, a diameter of the spring 10 which abuts against the vicinity of the hole 11 need to be enlarged, whereby the ferrule 9 and, as a result, the optical plug 1 becomes larger.
Or, if the optical fiber 8 is removed from the base portion 13 and then the optical fiber 8 is returned again after the directing member 5 is turned, the workability is not good.
The problems mentioned above occur not only in the optical ring network and in the optical connector but also in a hybrid connector in which an electric connector and an optical connector are integrated.
In view of the foregoing, an object of the present invention is to provide an optical connector capable of changing a leading-out direction of an optical fiber without hindering transmission of the light in the optical fiber, an optical ring network including the optical connector, and a hybrid connector.
In order to achieve the above-described object, as a first aspect of the present invention, an optical ring network includes: optical connectors attached to respective processing units; and optical fibers to connect the optical connectors in series in a ring, wherein at least one of the optical connectors includes: a ferrule provided at an end of the optical fiber; a housing having an accommodating chamber to pivotably accommodate an end portion, including the ferrule, of the optical fiber; and a directing member to be secured to the ferrule for directing the optical fiber led out from the housing.
As a second aspect of the present invention, in the structure with the above first aspect, the optical ring network further includes: a hybrid connector having an electric connector having an electrical housing; and an electric terminal to be accommodated in the electrical housing, wherein the optical connector having the ferrule to which the directing member is secured is fitted in the electrical housing.
As a third aspect of the present invention, an optical connector includes: an optical fiber; a ferrule provided at an end of the optical fiber; a housing having an accommodating chamber to pivotably accommodate an end portion, including the ferrule, of the optical fiber; and a directing member to be secured to the ferrule for directing the optical fiber led out from the housing.
As a fourth aspect of the present invention, in the structure with the above third aspect, the directing member is substantially cylindrical.
As a fifth aspect of the present invention, in the structure with the above fourth aspect, the directing member consists of a first casing and a second casing to couple with each other and a slip preventing means to prevent the first and second casings from slipping is provided on each of the first and second casings.
As a sixth aspect of the present invention, in the structure with the above third aspect, the directing member has a U-shaped cross section by having a circular arc portion and a pair of straight portions continuing from respective circumferential ends of the circular arc portion in parallel to each other and has an engaging portion to engage the optical fiber so as to restrict the optical fiber from separating from the circular arc portion.
As a seventh aspect of the present invention, in the structure with the above third aspect, the ferrule and the directing member have a displacement restricting means to restrict a relative displacement therebetween.
As an eighth aspect of the present invention, in the structure with the above third aspect, a plurality of said accommodating chambers are provided in the housing correspondingly to a plurality of said optical fibers and a plurality of said ferrule to which the respective directing members are secured are pivotably accommodated in the respective accommodating chambers.
As a ninth aspect of the present invention, in the structure with the above eighth aspect, each of the directing members has a different curvature.
As a tenth aspect of the present invention, a hybrid connector includes: the optical connector with any one of the above third to ninth aspects; and an electric connector having both of an electrical housing having a fitting portion for the optical connector and a plurality of electric terminals provided in the electrical housing.
According to the above-described structure of the present invention, the following advantages are provided.
(1) The optical ring network has the optical connector useful for connection of the units wherein a leading-out direction of the optical fiber led out from the optical connector have to be restricted. Because the directing member is secured to the ferrule and the ferrule is pivotable in the accommodating chamber, even if a leading-out direction is changed, distortion does not arise on the optical fiber. And, the leading-out direction of the optical fiber can be changed without bringing about bad influence on the light (i.e. an optical signal) with the optical ring network having the optical connector. Further, there exists no bad influence on the workability.
(2) The optical ring network has the hybrid connector useful for connection of the units wherein a leading-out direction of the optical fiber led out from the optical connector have to be restricted. Accordingly, this invention has the same effect as the above.
(3) Because the directing member is secured directly to the ferrule and the ferrule is pivotable with respect to the accommodating chamber, distortion of the optical fiber can be prevented. And, because a leading-out direction of the optical fiber can be easily changed, workability is improved. Consequently, the optical connector capable of changing a leading-out direction of the optical fiber without bringing about bad influence on the light (i.e. an optical signal) transmitted with the optical fiber. Further, there exists no bad influence on the workability.
(4) Because the directing member is secured to the ferrule and is formed cylindrically, the bent portion of the optical fiber can be protected in a preferable state.
(5) Because the directing member consists of the first and second casings and further the casings are provided with the slip preventing means, the bent portion of the optical fiber can also be protected in a preferable. And, workability in assembling the optical connector can be improved.
(6) A bent portion of the optical fiber can be protected in a suitably bent state without undesirable influence on the light (an optical signal) transmitted by the optical fiber. Further, since the optical fiber can be held by the engaging portions in turn, the optical fiber can be assembled to the directing member with better workability.
(7) Because a relative displacement between the directing member and the ferrule is restricted by the displacement restricting means, the ferrule and the directing member can be secured.
(8) Because a plurality of ferrules to which the respective directing members are secured are accommodated in the respective accommodating chambers pivotably, the optical connector having a plurality of optical fibers can be dealt with.
(9) Because the directing members are formed with respective curvature, degree of freedom of leading-out direction of the optical fiber can be increased. Also, handling of the optical fibers at its storage or transportation can be improved.
(10) The hybrid connector having the optical connector is provided, wherein the ferrule fixedly provided with the directing member is accommodated in the accommodating chamber of the housing of the optical connector. Accordingly, the hybrid connector which can change a leading-out direction of the optical fiber without bringing about bad influence on the light (i.e. an optical signal) transmitted with the optical fiber can be provided.
The above and other objects and features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings.